Leesburg is the county seat of Loudoun County, Virginia. It was built in 1740 and is named for the Lee family, early leaders of the town and ancestors of Robert E. Lee. In the War of 1812, it was a refuge for important federal documents evacuated from Washington, DC, and in the Civil War, it changed hands several times.
The town is situated at the base of Catoctin Mountain and adjacent to the Potomac River, 33 miles northwest of Washington, D.C., for which it has largely become a commuter suburb. Its population was 42,616 as of the 2010 census and an estimated 53,727 in 2019. It is Virginia's largest incorporated town within a county.